Control apparatus



June 27, 1933. F. H. KROGER CONTROL APPARATUS Filed y 29, 1929 66 x a: mm mm ATTOR N EY FRED H. KROGER BY I l l l l l ll Patented June 27, 1933 UNITED STATES PATENT; OFFICE FRED H. KROGER, OF RIDGEWOQD, JERSEY CONTROL APPARATUS Application filed May 29,

therefor in such a manner that said energizing circuits can be opened or closed from the point of control when it is desired that the transmitter be put into or out of use.

Furthermore in apparatus known heretofore separate lines have been provided to carry the energizing current to the relays adapted to open and close the energizing circuits at the transmitter end.

The primary object of this invention is to provide a novel arrangement in which a single conductor connecting the transmitter to the point of control in addition to carrying the keying pulsations from the keying deviceto the transmitter also serves as a conductor for the energy necessary to control the relay operated switches in the energizing circuits for the filaments and the plate of the transmitter.

Briefly and broadly the above object is attained by the use of a relay including a solenoid winding in the line associated with an armature having a large inertia in such a manner that when the solenoid is energized by closing a switch in the line the armature closes a circuit connecting a contact closing relay actuating winding in series with a source of direct current. The last named relay is arranged to close switches in the circuit feeding alternating current to the transmitter plate rectifier circuit and the filaments of the transmitter tubes. Due to the inertia of the armature associated with the winding in the-line the reversing currents in the line due to keying of the transmitter will not cause thespring biased armature to move into a position to reverse the current through 7 the circuit including the contact actuating relay winding. A high resistance is associated between the first named contact and the armature in such a manner that a sufiicient amount of current flows through the con tact actuating solenoid at all times when the 1929. Serial No. 367,086.

line switch is closed to hold the contacts in 1? the power supply lines for the transmitter n a closed position. When the line switch s opened the contact actuating relay wind: mg is deenergized and the contacts in the power supply lines open either by spring action or by gravity.

Numerous other objects and advantages will become apparent from the specification and therefrom when read in connection with the drawing in which the single figure shows the at present preferred form of my control apparatus.

Referring in particular to the drawing, A is a transmitter, B is a rectifier and filter for supplying plate, potential to the transmitter C is the relay having the armature with a large amount of inertia and the contact actuating solenoid arranged to close the circuit connecting the sourceof power to the rectifier B. D is the energizing source for the line and the telegraph key while E is the standard. key relay associated with the grid circuit ofthe transmitter. The transmitter shown merely for purposes of illustration comprises a thermionic oscillation generator 1 having its filament energized by means of a secondary windlng 2 of a transformer 3 havlng its primary winding 4 connected across the lines 5, connected with the alternating current source for the transmitter.

An output circuit including a tank circuit having an inductance 7 tuned by a condenser 8 is connected between the anode of tube 1 and the filament thereof. Energy. from this tank circuit is delivered to the aerial 9 through an inductance 10 coupled to the inductance 7 in the tank circuit. The aerial 9 is grounded at G. Sustained oscillations inthe generator 1 are insured by the. coupling between the inductance 11 in the gridcathode circuit of land the inductance 7 in the anode cathode circuit of 1. 4 Keying of the transmitter is accoinplished by short .circuiting the leak '12 and condenser 13 in the grid circuit. Current for the space current anode circuit of the osthe primary winding 19 of whichis adapted to be connected to the main power source. The anode of thermionic tubes 14 and 15' are connected to opposite ends of the secondary winding of a transformer 21 the primary winding 22 of which is also adapted to be connected to the main power source. The energizing circuit for the anode of the transmitter is completed through a conductor connecting the filaments 16 ofthe rectifier tubes to the anode of 1 and a conductor connecting.

the midpoint of the secondary winding 22 of the rectifier supply transformer tovground. An inductance 23 in the first named conductor and an inductance 24 in-the last named con-' ductor are provided to prevent radio frequencies set up by the oscillation generator 1 from being introduced into the rectifier circuits. A condenser 25 betweenthe anodeof 1 and-the tank circuit 6- prevents the anode potential from being applied across the filament of 1. Fluctuations in the current supplied to the anode of the high frequency generator from the full Wave rectifier are smoothed out by means of a condenser 26 connected between the filaments of the rectifier and ground. The anode current circuit is completed through a conductor connecting the midpoint of a palrof series condensers connected across the filament of the generator to ground; Contacts 30 in the alternating current supply line connected tothe armature, not shown, of a winding 31 are adapted to be closed by said armature when the circuit connecting the winding 31 in'series with the direct currentsource 32 1S closed.

This circuit includes an armature 33 having a weight arranged in such a manner as to tend to draw this armature towards contact 34while a: spring 35 tends to draw the armature towards contact' 36.- A, fuse 37 in circuit with the power source when the armature closes the contact at 36 prevents damage A high resistance 39 is shunted around armature-33 in such a manner as to allow'sufiicient current to flow in winding-31 to hold contacts 30 in the-closed position even when armature 33 leaves contact .34 for short periods during keying of the transmitter. Armature 33 isactuatedjby a winding 40, in

. series with the mainlineand energized by current'from the main line power source 41 having its 'midpoint connected to ground when the switch 42 is closed. WVhen switch 42 is closed current fiows through the wind ring 40. The winding attracts armature 33 to closed contact 34. Current flowing through the circuit closed by 34 energizes winding 31 to close the contacts 30, thereby energizing the cathode and anode circuits of the transmitter.

The key apparatus for the transmitter includes as shown at E an armature 44 arranged to close a contact'and short circuit the grid leak 12 and condenser 13 in the grid circuit of the oscillation generator thereby interrupting operation of the generator 1 in accordance with the signals to be sent out. The armature 44 is adapted to be actuated by a circuit 45 including winding 46 and a source of power 47. This last named circuit is in turn arranged to be opened and closed by the armature 49 of polar relay 5O actuated by and in accordance with current pulsations from the battery 41 flowing in the main line during keying operation. The

7 main line circuit is completed by grounding the one end of winding 50. e I

Returning to D the telegraph key relay 53 is included in a circuit 54 which includes a solenoid 55 arranged to close its armature 56 to make and break contacts 57 and 58 in accordance with themanner in which key 53 is operated. When the contact 57 is closed by the armature current flows through the main line in one direction whereas when the contact 58 is closed the direction of flow of current in the main line is reversed. To insure that contact 58 is closed when key53 is opened a spring 60 is connected to the armature of the key relay in such a manner as to close contact 58 when the solenoid winding 55 is deenergized. r V

. Briefly the operation of' the apparatus is as'follows: I I h To start the transmitter, key 42 is closed. This allows a currentto fiow through the main line. \Vinding 40 is energized attracting armature 33 to close contact 34. This puts winding 31 in series with the source of direct current 32. When winding 31 is energized contacts 30 are closed putting the primary windings of transformers 3, 18 and 21 in'series with the main alternating current supply and current is furnished to the filaments of the rectifier and the oscillation generator and rectified direct'current is provided for the plate of the oscillation generator.

To send out signals the telegraph key 53 is manipulated. This sends reversing current through the line operating polar relay 50. Relay 50 makes and breaks the circuit including relay winding 46 Which'relay in turn makesand breaks the circuit including contact 36. The resistance 39 connectedbetween the contact 34 and "armature 33 allows sufficient holding current to "flow through winding 31 to keep contacts 30 closed duringthe signal keying operation.

To stop the transmitter, key 42 is opened.

Although for purposes of illustration I have shown the at present preferred form of my invention as being applied to a transmitter and rectifier'therefor of a well known type it will be understood that my invention is not limited to such use but may be used in various other arrangements in which it is desirable to control from more or less remote points apparatus to be used in signalling.

I claim:

1. The combination of a transmitter having a thermionic oscillation generator, a potential source for the electrodes of said generator keying means connected with said thermionic generator, a keying relay for said keying means, means including a single conductor connecting said relay to said keying means, switching means for said potential source, and means including a relay winding in series with said conductor for controlling said switching means.

2. A transmitter adapted to be controlled from a remote point comprising a thermionic tube having coupled input and output circuits, a source of potential for energizing said circuits, a switch interposed between said source and said circuits, keying means connected with one of said circuits, means for rendering said transmitter operative and for actuating said keying means from a remote point comprising, a line connected between said transmitter and said remote point, a source of potential connected in series with said line, a quick acting magnetic relay having a winding in series with said line at the transmitter terminal thereof, actuating means operatively interposed between said winding and said keying means, a slow acting magnetic relay including a winding in series with said line, said winding forming the driving element of a magnetic relay, a key in said line at said remote point, and an armature associated on the one hand with said last named winding and on the other hand with the switching means between said potentialsource and the circuits of said tube. 3. A remote controlled transmitter comprising a thermionic tube having input and output circuits and a filament heating circuit. a source of alternating current potential for energizing all of said circuits, rectifying means interposed between said source and said input and output circuits, a switch interposed between said source and said filament heating circuit and between said source and said rectifier, keying means connected with one of said circuits, and means for rendering said transmitter operative and for actuating said keying means from a remote point comprising, a hneconnecting said transmitter and said re mote point; a source of potential connected with said line, a quick acting magnetic relay having a winding in series with said line, actuating means inter.- posed between said winding and said keying means, a slow acting magnetic relay including a 'windinginiseries with said line, and actuating means interposed between said last named winding and the switching means between said potential source and the circuits of said tube. y r I 4. In signalling means, a thermionic tube having input and output electrodes and input and output circuits connected therewith and a cathode heating circuit, a source of alternating current, a thermionic rectifier interposed between said source and said input and said output circuits, a transformer connected between said source and said cathode heating circuit, keying means associated with said input circuit, switching means interposed between said alternating current source and said rectifier and said transformer, and means for controlling said,

transmitter from a remote point comprising, a conductor between said transmitter and said remote point, an energizing source comprising a battery having its midpoint grounded and its terminals adapted to be connected in series with said line, said key being adapted to send a negative impulse over said line in one position and a positive impulse over said line in another position, a key in said line, a quick acting magnetic relay interposed between said keying means and said line, and a slowacting magnetic relay interposed between said line and the switch between said alternating current source and said rectifier and said transformer.

5. The combination of a transmitter having a thermionic oscillator tube, having input and output electrodes and coupled input and output circuits connected therewith and a. cathode circuit, a source of alternating current, a thermionic rectifier interposed between said source and said input and said output circuits, a transformer interposed between said source and said cathode circuit, a switch interposed between said source and said rectifier and said transformer, keying means connected with said input circuit, and means for rendering said transmitter operative from a remote point and for keying the same comprising, a conductor between said transmitter and said remote point, an energizing source comprising a battery having its midpoint grounded and its terminals adapted to be connected in series with said line so that the polarity of the current in said line may be reversed, a switch in said line, a magnetic relay winding in said line, an armature associated with said winding and connected with the switch between said alternating current sourceand said rectifier and vsaid transformer, said relay being adapted to close said last named switch toenergize said tube circuits when said line switch is closed, a quick acting magneticv relay interposed between said key-. ing means 'and'psaid 'line,=and a manually actuated keying means for alternately reversing the connection between said line and its energizing source, thereby actuating said quick acting relay. 1 I FRED KROGER. 

